Cellulose-ether solvent and composition



Patented A... s, 1923.

STA ES PATENT OFFICE.-

sTEwARr J. CARROLL, or noonnsrnn, ivnw YORK, ASSIGNOR TO EASTMAN KODAKCOMPANY, or noonnsrnn, NEW max, A CORPORATION or NEW YORK.

OELLULOSE-ETHEB SOLVENT AND COMPOSITION.

No Drawing.

A solvent which will dissolve such large proportions of. celluloseethers that thick or viscous flowable solutions may be obtained for usein plastic and film making arts. .Another object of my invention is toprovide a cellulose ether solution which may be manufactured intostrong, flexible, transparent film on the machines and by the methodsnow in use.

In U.- S. Patent No. 1,188,376, Lilienfeld,

' 2 June 20, 1916, there are disclosed. a series of alkyl ethers ofcellulose.- Certain of these are practically insoluble in water, and myinvention'relates, but is not limited, to the ethers having thatproperty. .While the,

ethers form thin solutions in the lower mono-' hydroxy aliphaticalcohols or furfural, it. has been-found that such single solvents by;

themselves do not dissolve a suflicient -proportion of the ethers tomake a desirably thick flowable composition or dope, such as may be usedin the 'manufacture of photographic film base by customary methods, or

in the other plastic arts. i I have discovered that. an adequatelystrongand useful solvent may be. prepared by mixing furfural with one ormore of the lower monohydroxy aliphatic alcohols. For I example, I mayuse from 90 to 50 parts of furfural and 10 to 50 parts by' weight of thealcohol, say methyl or ethyl alcohol as an illustration. In thepreferred form of my invention, I use equal parts by weight of furfuraland methyl or ethyl alcohol. While the amount of ether that may bedissolved in such mixed solvents maybe varied as de-v sired over a largerange, it is noted, for the Application filed na 24,

ters Patent-us:

1921. Serial No. 472,272.

sake of example, that 1 part by weight of the dope, such, for instance,,as triphenyl or tricresyl phosphate, camphor, etc. In the formation ofthe film a considerable amount of furfural is left therein, due to itsrelatively low volatility. It imparts useful properties to such film.

The ingredientsare of the ordinary commercial type and sufficientlypurified for the processoffilm manufacture, soas to give a dope yieldingfilms having the proper relative freedom from color; Theviscous-flowable dope above described'can be used in connection with theusualsfilm-forming apparatus without-theriecessity of expensivealterations in the latter. By lower monohydroxy aliphatic alcohol Iinclude one havin less than six carbon atoms.

aving thus described my invention, what I claim as new. and desire tosecure by Let 1. A composition of inatter, comprising cellulose etherdissolvedfin a mixture containing furfural and a lower monohydroxyaliphatic alcohol.

2. A viscous flowable gcomposition, comprising an alkyl ether ofcellulose dissolved in a solvent containing from 90 to 50 parts byweight of furfural'and 10 to 50 parts of a lower monohydroxy aliphaticalcohol.

"3. A composition of matter, comprising water-insoluble ethyl cellulose,furfural and methyl alcohol. 4. A composition of matter comprisingcellulose ether and furfural. 5. A composition of matter cofiiprisingWater-insoluble ethyl cellulose and furfural.

.6. As an article of manufacture, a deposited or flowed flexible filmcontaining cellulose ether and furfural.

A Signed, at Rochester, New York, this 14th

